The human body is often likened to a high-performance machine.
But it is so much more than that. It works 24 hours a day for decades without (for the most part) needing regular servicing or the installation of spare parts.
It runs on water and a few organic compounds, is soft and rather lovely, reproduces itself with enthusiasm, makes jokes, feels affection and appreciates a red sunset.
How many machines do you know that can do any of that? There is no question about it. You are truly a wonder.
And how do we celebrate the glory of our existence? Well, for most of us by exercising minimally and eating maximally.
Think of all the junk you throw down your throat and how much of your life is spent in a near vegetative state in front of a glowing screen.
Yet in some kind and miraculous way our bodies look after us, extract nutrients from the miscellaneous foodstuffs we push into our faces and somehow hold us together.
The human body works 24 hours a day for decades without (for the most part) needing regular servicing or the installation of spare parts. Pictured is Bill Bryson
Even when you do nearly everything wrong, your body maintains and preserves you. Most of us are testament to that in one way or another.
Five out of six smokers won’t get lung cancer. Most of the people who are prime candidates for heart attacks don’t get heart attacks.
Every day, it has been estimated, between one and five of your cells turns cancerous and your immune system captures and kills them. Think of that.
A couple of dozen times a week, well over 1,000 times a year, you get the most dreaded disease of our age, and each time your body saves you.
Our bodies are a universe of 37.2 trillion cells operating in more or less perfect concert more or less all the time.
Every day, it has been estimated, between one and five of your cells turns cancerous and your immune system captures and kills them. Think of that
An ache, a twinge of indigestion, the odd bruise or pimple is about all that in the normal course of things announces our imperfectability.
There are thousands of things that can kill us – slightly more than 8,000, according to the World Health Organisation – and we escape every one of them but one. For most of us, that’s not a bad deal.
‘Feel this,’ the doctor is saying to me. We are in the dissecting room at the University of Nottingham Medical School and Dr Ben Ollivere is directing my attention to a piece of detached tubing in the upper chest of a male body.
I am struck by a powerful thought. In the dissecting room, the human body is no longer a wondrous piece of precision engineering. It’s meat.
Ben instructs me to stick my gloved finger into the interior of the tube and feel it. It is stiff, like uncooked pasta.
I have no idea what it is. ‘The aorta,’ Ben says, with what seems like pride.
I am frankly amazed. ‘So that’s the heart?’ I say, indicating the shapeless lump beside it.
A couple of dozen times a week, well over 1,000 times a year, you get the most dreaded disease of our age, and each time your body saves you. Our bodies are a universe of 37.2 trillion cells operating in more or less perfect concert more or less all the time
Ben nods. ‘And the liver, pancreas, kidneys, spleen,’ he says, pointing out the other organs of the abdomen in turn.
Ben is an old friend and a distinguished academic and trauma surgeon. There isn’t anything in the human body that doesn’t fascinate him.
‘Just consider all that the hand and wrist do,’ he says. He tugs gently on an exposed tendon in the cadaver’s forearm up near the elbow and, to my surprise, the little finger moves. Ben smiles at my startlement and explains that we have so much packed into a small space in the hand that a lot of the work has to be done remotely, like strings on a marionette.
‘The wrist is just a thing of Beauty,’ he goes on. ‘Everything has to go through there – muscles, nerves, blood vessels, everything – and yet it has to be completely mobile at the same time.
‘Think of all the things your wrist has to do – take a lid off a jam jar, wave goodbye, turn a key in a lock, change a light bulb. It’s a magnificent piece of engineering.’
Ben’s field is orthopaedics, so he loves bones and tendons and cartilage the way other people love expensive cars or excellent wines. ‘See that?’ he says, tapping a small, smooth, very white obtrusion at the base of the thumb, which I take to be a bit of exposed bone.
‘No, it’s cartilage,’ he corrects. ‘Cartilage is remarkable, too. It is many times smoother than glass: it has a friction coefficient five times less than ice.
‘Imagine playing ice hockey on a surface so smooth that the skaters went 16 times as fast. That’s cartilage.
‘But unlike ice, it isn’t brittle. It doesn’t crack under pressure as ice would. And you grow it yourself. It’s a living thing.
There are thousands of things that can kill us – slightly more than 8,000, according to the World Health Organisation – and we escape every one of them but one. For most of us, that’s not a bad deal
‘None of this has been equalled in engineering or science. Most of the best technology that exists on Earth is right here inside us.’
Before we move on, Ben examines the wrist more closely for a moment. ‘You shouldn’t ever try to kill yourself by cutting your wrists, by the way,’ he says.
‘All of those things going in are wrapped in a protective band called a fascial sheath, which makes it really hard to get to the arteries.
‘Most people who cut their wrists fail to kill themselves, which is no doubt a good thing.’
He is briefly thoughtful. ‘We are designed not to die.’ This seems a slightly ironic thing to say in a big room full of dead bodies, but I take his point.
We tend to think of our bones as inert bits of scaffolding, but they are living tissue too. They grow bigger with exercise and use just as muscles do.
‘The bone in a professional tennis player’s serving arm may be 30 per cent thicker than in his other arm,’ Margy Pratten, an associate professor of anatomy told me – citing Rafael Nadal as an example.sonos sonos One (Gen 2) - Voice Controlled Smart Speaker with Amazon Alexa Built-in - Black read more
Look at bone through a microscope and you will see an intricate array of productive cells just as in any other living thing. ‘Bone is stronger than reinforced concrete,’ says Ben, ‘yet light enough to allow us to sprint.’ All your bones together will weigh no more than about 20 lb (nine kilograms), yet most can withstand up to a ton of compression.
‘Bone is also the only tissue in the body that doesn’t scar,’ Ben adds. ‘If you break your leg, after it heals you cannot tell where the break was. There’s no practical benefit to that. Bone just seems to want to be perfect.’
Even more remarkably, bone will grow back and fill a void.
‘You can take up to 30 centimetres of bone out of a leg, and with an external frame and a kind of